Depletion of Luminal Pyridine Nucleotides in the Endoplasmic Reticulum Activates Autophagy with the Involvement of mTOR Pathway
Figure 1
NADPH depletion induced by metyrapone is sufficient to promote autophagy. HepG2 cells were treated with different amount of metyrapone (10 μM–100 μM) for 1 h at 37°C. (a) Cell lysates were analysed by Western blot by immunoreacting with antibodies against LC3, procaspase 3, PARP, and GAPDH, respectively. The relative density of both the lower band of LC3/GAPDH and PARP/GAPDH were plotted. (b) Cell viability was assessed by counting the cells both permeable and nonpermeable for trypan blue. About 95% of the cells were nonpermeable for trypan blue. (c) Cell viability was followed by using Cell Titer-Blue Assay and the relative cell viability was represented after 1-hour long metyrapone treatment. As positive controls cells were treated with tunicamycin (TM—25 μM) for 2 hours combined with/without 2-hour long 3-methyladenine pretreatment (3-MA—10 mM).
